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/*字符串 DESede(3DES) 加密*/
import java.security.Security;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
public class DES3 {
private static final String Algorithm = "DESede"; //界說加密算法,可用
// DES,DESede,Blowfish
// keybyte為加密密鑰，長度為24字節
// src為被加密的數據緩沖區（源）
public static String encryptMode(byte[] keybyte, byte[] src)
{
try
{
// 生成密鑰
SecretKey deskey = new SecretKeySpec(keybyte, Algorithm);
// 加密
Cipher c1 = Cipher.getInstance(Algorithm);
c1.init(Cipher.ENCRYPT_MODE, deskey);
// 開端加密運算
byte[] encryptedByteArray = c1.doFinal(src);
// 加密運算以後 將byte[]轉化為base64的String
BASE64Encoder enc = new BASE64Encoder();
return enc.encode(encryptedByteArray);
}
catch (java.security.NoSuchAlgorithmException e1)
{
e1.printStackTrace();
}
catch (javax.crypto.NoSuchPaddingException e2)
{
e2.printStackTrace();
}
catch (java.lang.Exception e3)
{
e3.printStackTrace();
}
return null;
}
// keybyte為加密密鑰，長度為24字節
// src為加密後的緩沖區
public static byte[] decryptMode(byte[] keybyte, String src)
{
try {
// 生成密鑰
SecretKey deskey = new SecretKeySpec(keybyte, Algorithm);
// 解密
Cipher c1 = Cipher.getInstance(Algorithm);
c1.init(Cipher.DECRYPT_MODE, deskey);
// 解密運算之前
BASE64Decoder dec = new BASE64Decoder();
byte[] encryptedByteArray = dec.decodeBuffer(src);
// 解密運算 將base64的String轉化為byte[]
return c1.doFinal(encryptedByteArray);
} catch (java.security.NoSuchAlgorithmException e1) {
e1.printStackTrace();
} catch (javax.crypto.NoSuchPaddingException e2) {
e2.printStackTrace();
} catch (java.lang.Exception e3) {
e3.printStackTrace();
}
return null;
}
// 轉換成十六進制字符串
public static String byte2hex(byte[] b) {
String hs = "";
String stmp = "";
for (int n = 0; n < b.length; n++) {
stmp = (java.lang.Integer.toHexString(b[n] & 0XFF));
if (stmp.length() == 1)
hs = hs + "0" + stmp;
else
hs = hs + stmp;
if (n < b.length - 1)
hs = hs + ":";
}
return hs.toUpperCase();
}
public static void main(String[] args)
{
// 添加新平安算法,假如用JCE就要把它添加出來
Security.addProvider(new com.sun.crypto.provider.SunJCE());
final byte[] keyBytes = { 0x11, 0x22, 0x4F, 0x58, (byte) 0x88, 0x10,
0x40, 0x38, 0x28, 0x25, 0x79, 0x51, (byte) 0xCB, (byte) 0xDD,
0x55, 0x66, 0x77, 0x29, 0x74, (byte) 0x98, 0x30, 0x40, 0x36,
(byte) 0xE2 }; // 24字節的密鑰
String szSrc = "This is a 3DES test. 測試";
System.out.println("加密前的字符串:" + szSrc);
String encoded = encryptMode(keyBytes, szSrc.getBytes());
System.out.println("加密後的字符串:" + encoded);
byte[] srcBytes = decryptMode(keyBytes, encoded);
System.out.println("解密後的字符串:" + (new String(srcBytes)));
}
}
